A good example is how air pollution is known to increase the risk of developing asthma.

According to a new study, it doesn’t just end at developing the condition, it also makes controlling it more difficult.

In the study the researchers surveyed 481 people about their asthma symptoms and compared that data to information about local levels of ozone, nitrous oxide, and particulate matter. These are all factors that contribute to poor air quality. What they found is that levels of ozone and particulate matter were strongly linked to poorer asthma control, with long term exposure increasing the risk of having uncontrolled asthma by almost seventy percent.

Clearly this is not a problem that is easily controlled. One suggestion I have is that during summer months those with asthma and respiratory problems need to be particularly concerned about avoiding outdoor exposure on very hot and smoggy days.